| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 1469993 | Corrosion Science | 2011 | 6 Pages |
Fe-based amorphous coatings with a composition of Fe49.7Cr18Mn1.9Mo7.4W1.6B15.2C3.8Si2.4 have been prepared on a mild steel substrate by High velocity air fuel (HVAF) and High velocity oxygen fuel (HVOF) processes. The microstructure and corrosion resistance in 3.5 wt.% NaCl solution of the coatings prepared by the two processes were comparatively studied. It was found that the two coatings exhibit dense structure with the porosity of 0.4% and compact bonding with the substrate. However, HVOF coating contains higher oxygen content than HVAF coating, resulting from the formation of significant oxide contours between the partially melted particles in HVOF process. Electrochemical polarization tests and electrochemical impedance spectroscopy (EIS) analysis indicate that the HVAF coating has better corrosion resistance than the HVOF coating. The preferential corrosion along the oxide contours thus providing efficient diffusion channels for electrolyte accounts for the poor corrosion resistance in HVOF coating. The present results demonstrate that HVAF with less cost can be a promising spray process to fabricate the Fe-based amorphous coating for industrial applications.
Research highlights► Compact and hard Fe-based amorphous coatings with extremely low porosity were successfully prepared. ► The microstructure and corrosion resistance of the coatings have been comparatively studied. ► HVAF technique with less using-cost (compared to HVOF) can be a promising spray process to fabricate Fe-based amorphous coatings for industrial applications.
